The primary criterion of Scripture is its use in the liturgy, specifically its use as the key readings in the liturgy. From this comes the essential criterion of canonicity, as well as the other uses of Scripture in the church.
Only some books are read and not others. Because the question of what is read must be made: one either reads a given book, or not, the question is inescapable. The practice of course derived from the synagogue with its own practice of readings. Immediately one notices some qualifications necessary.
First, there are readings from non-biblical literature. These are most often found in the morning office, as patristic readings. They were prescribed by the Rule of Saint Benedict, and are found in other liturgies as well. Recently some Anglican liturgies have made their use optional. Special services, especially weddings, often find such readings.
We can note some facts about these additional non-Scriptural readings which explain why, despite their use in the liturgy, they are not thereby Scripture. They arose only later, and always surrounded with the rule that they can augment, but never replace, the Scriptural readings. Second, they are limited to only some services and not used in others, while Scriptural readings are used in nearly all services.
A second qualification is the use of hymns from non-biblical sources, especially in contexts where biblical texts are normally found. For example, in the Anglican office one finds the use of the Te Deum and the Gloria in Excelsis as canticles for some days and not others. We should note, however, that in the Roman Office, the Te Deum has its own place, and the Gloria is not found in the office at all. Perhaps even more interesting is the extensive use of "canons" of antiphons in the Orthodox services, which have come to replace almost entirely the singing of the biblical canticles with which they were associated.
However, we can see that these hymns are used as the expression of the worshippers: quite rather than being read to the worshippers, they are sung by the worshippers themselves as their own prayer. And, most importantly, while some of them have come to replace or even supplant biblical texts, they are not allowed to introduce upon the readings in the liturgy proper.
So the liturgy marks out, by particular forms, certain texts, which are read from the Scriptures at particular moments, and surrounded by particular ceremony and responses. These texts are taken from the normative canon of Scripture, and it is this selection which determines the canon.
Choice of Books
The texts chosen vary from church to church. Different churches have made different judgments about canonicity, with different reasons. Broad agreement was reached fairly early, with disagreement arising in the sixteenth century about the "apocrypha": Jewish texts in the Greek and Latin Bibles but not in the Hebrew.
One can judge that what a church reads in worship, as a canonical reading, is what that church takes to be canonical. But there are some constant worries. For example, Anglicans have always read from the apocrypha, but have a rule that the texts thus read are not to establish points of doctrine. The Orthodox have always admitted the Revelation of John as canonical, but do not read it in services.
So the actual practice of churches is a bit fuzzy. I judge, however, that the choice to read a text in church as scripture establishes its canonicity for that community; while a decision not to read it is determinitive neither way. So we must say that the apocrypha are canonical for Anglicans, and we must understand the decision not to base doctrine upon them in some other way. The Orthodox, who insist that the Revelation is canonical, must be taken at their word, though it is not read in services.
For every church cannot read everything, or at least, thus has been the case.
Choice of Readings
The choice of readings offers the fear that we establish a canon within the canon. Such choices are made often for practical reasons, but an examination of lectionaries will show that other concerns are also often present.
Sometimes a text is excluded because it is ugly: this is often the case with various psalms in various liturgies. More often, it is excluded from reading because, essentially, the compilers of the lectionary do not know how it could be read and understood as Scripture by their community.
They express, thus, a sort of half-doubt about canonicity. They do not wish to read texts about which the worshipping community will react with marked hostility; in this they reflect (or try to) the judgments the community itself makes. It is just this which is invoked to exclude the Revelation of John from Orthodox liturgy; and likewise, one can imagine just such motives behind the particular omissions from various New Testament epistles in the Daily Office lectionary of the Episcopal Church.
However, the lectionary compilers are not excluding such readings from the church. One finds that, in fact, no broad exclusion is made; merely that the particular reading is not included in the lectionary. But the actual practice of the churches allows readings outside the lectionary for various purposes; importantly, no judgment is made that the text is in principle incapable of being used as scripture, merely that it is pastorally inadvisable in the particular setting.
One must always be wary, however, that a continued practice of this sort does result, ultimately, in a loss of canonicity for that community. Lectionary authors are therefore advised to be extremely careful with such cases.
The readings are marked by particular honorifics. Most notably in the West is the acclamation "thanks be to God" after readings; in recent years this is preceded by the declaration of the reader: "The Word of the Lord." Moreover, liturgy renders an honorific immediately by the near constant use of Scripture in liturgy. Nearly every service has a reading, even if reduced to a single sentence or two. (And, in those cases, it is still regarded as a reading.)
One finds directions about reading from dignified books, elevated platforms, surrounded by lights, and so forth. The reading of the Gospel, in particular, is associated with special honor played the Gospel book and the management of its reading in liturgy.
In these ways and more the church confesses something about the reading of Scripture. But most importantly, what it confesses is that Scripture should be surrounded by reverence. It should be treated as important, and this is crucial. Nothing is so strange to the liturgical worshipper as the fundamentalist preacher holding his Bible, with no actual reading having occurred, as he pages around in his sermon identifying bits and explaining them. It looks so undignified; the text is being made to serve the speaker. At no point can the text simply be heard.
The Puritans insisted that a homily should be associated with every reading, but Anglicans followed liturgical tradition in refusing. In particular, we trust that the reading, by itself, is capable of doing something. In not demanding a homily at each reading, we mark a conviction about the power of the text itself.
On the Use and Interpretation of Scripture: Index